DETECTION OF RESIDUAL DISEASE FOLLOWING BREAST-CONSERVING SURGERY

Background Assessment of completeness of tumour excision has become an integral part of breast-conserving surgery, but the accuracy of margi n analysis has been questioned. This study compared the results of res ection margin analysis with an examination of tumour bed biopsies and of the excised cavity wall. Methods One hundred and forty-four patient s underwent breast-conserving surgery for T1-2 N0-1 breast cancer. Fol lowing wide local excision, four bed biopsies were taken from the cavi ty wall which was then completely excised. The presence of invasive an d in situ disease at the inked resection margin (IRM) and in the adjac ent bed biopsies and cavity wall was recorded. Results Positive margin s and/or residual disease in either the bed biopsies or cavity wall wa s found in 62 (43 per cent) of 144 cases. Residual disease (invasive o r in situ) was present at the IRM in 39 specimens (27 per cent) and wa s present in 25 bed biopsy (17 per cent) and 39 cavity wall (27 per ce nt) specimens. These comprised different but overlapping groups of pat ients. Conclusion Margin analysis of wide local excision specimens is a poor predictor of completeness of excision. Routine resection and ex amination of the entire cavity wall increases the detection of residua l disease compared with examination of bed biopsies alone and is a use ful adjuvant to conventional margin evaluation.